Reciprocating compressors typically operate with valve plate assemblies that include a valve plate to which is affixed a suction valve and a discharge valve to control the intake and discharge of refrigerant gas. A valve plate gasket is typically installed adjacent the cylinder head and the cylinder block. Prior art designs include a separate discharge valve retainer for each bore in the compressor. Certain designs that employ a single discharge valve retainer include a large number of bend radii, requiring very accurate parts in order for the discharge valve to function properly. The large number of bend radii is required due to the arrangement of discharge ports on the valve plate.
Many of these assemblies are discussed in the prior art. For example, U.S. Pat. Nos. 4,867,650 ('650 patent) and 6,368,085 ('085 patent) disclose refrigeration compressors utilizing suction valves and valve plate gaskets comprising a single piece of steel. Slots in these suction valves are formed by slotting sheet of steel to form the valve and valve plate gasket and suction valve. For example, in the '085 patent, the slot is of variable width so as to allow for uniform finishing operations on the valve so as to reduce or prevent premature valve failure. These slots do not provide additional flow area through the valve for gas when the valve is open during a suction or intake stroke of the compressor piston.
Other assemblies such as one described in U.S. Pat. No. 6,382,927 position the valve plate assembly that position the valve plate relative to the cylinder head by utilizing pins projecting from the cylinder head which assists in the assembly, fit-up and handling of this plurality of components. What is needed is a design that not only simplifies the assembly and handling of the valve plate assembly, but that also improves the operating efficiency of the compressor. When this assembly is used in a semi-hermitic design, it provides the additional advantage of making disassembly and repair more convenient.